Duplicating with the aid of stencils



M y 33- I s. GESTETNER 1,906,374

DUPLICATING WITH THE AID OF STBNCiLS Filed Marc'nzo, 1931 2 Sheets-Sheet1 y 1 s. GESTETNER Y 1,906,374

DUPLICATING WITH THE AID 0F STENCJZLS v 2 Sheets-Sheet 2 Filed March 30..1931

Patented May 2, 1933 UNITED STATES PATENT OFFICE SIGEUID GES'IETNES, OFTOTTENHAM HALE, LONDON, ENGLAND, ASSIG-NOR, BY

IESNE ASSIGNMENTS, TO A. B. DICK COMPANY, OF CHICAGO, ILLINOIS, A CORPO-BATION OF ILLINOIS DUPLIOATING WITH THE AID OF STENCILS Applicationfiled March 30, 1931. Serial No. 526,462.

This invention relates to rotary stencil duplicating machines of thekind with WhlOh a relatively viscous or pasty ink is employed and inwhich the ink is distributed over the surfaces of a plurality ofnonorous 1nk1ng cylinders by which it is force through the openings inthe stencili the latter being nor- Y mally mounted on a exible stencilcarrier secured to endless bands in driving engagement with thecylinders by the rotation of which the stencil is caused to travel overthe surface of the inking cylinders, the impression-receiving materialbeing fed between one of these cylinders and a pressure roller.

Hitherto, with such machines, one end of the stencil,commonly describedas the stencil heading, is engaged by fastenin means provided 'on amember extending etween the flexible bands in contact with a silk sheet,oneend of which is also engaged with the membenin question, the otherend of the silk sheet being connected with a substantially rigid elementextending from one band to the other band and being connected, in turn,with a member also extending across the machine and spaced apart fromthe first-mentioned member in order to permit inkto be applied to thesurface of the cylinders, the second mentioned member being connected bya piece of flexible ink-impermeable materlal with the member on whichthe fastenin means for the stencil is provided.

ith this arrangement, hitherto it has been possible, in the event of theink being or becoming relatively fluid, particularly with high speeds ofoperation of the machine,

for ink to be thrown off the cylinders.

The object of the present invention is to provide means for preventingsuch a possibility.

' Accordin to the invention, with the sub-.

stantially rigid element connected with the end of the silk sheet remotefrom the stencil fastening means is hingedly connected a hinged flapadapted to extend from the member in question and to bridge over theopeng enabling ink to be supplied to the inkin cylinders.

lreferably, in accordance with the invention with the flap is associatedsprings adapted to constrain the flap to move into the position in whichit bridges or covers the opening and the springs in question are,preferably, so arranged that on moving the flap about its hingedconnection, in order to permit ink to be delivered on to the cylinders,it will be moved over its dead centre and retained in the open positionby the sprin Thus, in accordance with the invention, projections may beprovided on the flap, each of such projections engaging one end of aspring, the opposite end of which is connected with the rigidv memberextending across the machine and forming an abutment for the free edgeof the flap.

The connection between the ends of the flaps remote from theirconnection with the flap may each comprise a stirrup element adapted toengage a projection on one end of the rigid member in question, theprojection bein constituted by the end of a bolt whereby t e saidelement is secured in know manner to the flexible bands.

One construction in accordance with the invention will be illustrated byway of ex- .with the invention;

Figure 2 is a view in perspective illustrating the application of thedevice to the inking cylinders of such a machine;

Figure 3 is a front view in elevation of the machine with the device inthe position adapted to permit ink to be applied to the upper inkingcylinder;

' Figure 4 is a view of the device associated with a silk sheet, and

Figure 5 is an end elevation on an enlarged scale of the flap and itsassociated parts.

The duplicating machine illustrated is generally of the characterdescribed in the United States specification No. 700,031 and in Figures1, 2 and 3 of the drawings, 1 and 1a represent, respectively, the upperand lower inking cylinders. These cylinders are provided with spindles 2and 2a which, as

shown in Figures 1 and 2, are en aged in bearings in the side members 3whic are secured to a base plate 4 and form therewith the main frame ofthe machine.

By means of the handle 5.0n the spindle 6 on which is mounted the pinion7, meshing with the spur wheel 8 mounted upon the spindle 2a of theinking cylinder 1a, the said inking cylinder may be rotated andconsequence of the engagement of the Plus 9 in holes provided in theflexible members 10, corresponding motion is imparted to the inkingcyllnder 1.

With the inking cylinders are aranged to cooperate, in the normaloperation of the machine, a pair of waver rollers 11, the spindles 12 ofwhich are engaged in slots 13 in the blocks'14 which are slidablymounted in slots in the ends of the pivoted lever 15 the books beingconnected together by a spring 16 adapted to force the waver rollersinto contact with the inking cylinder.

This lever is mounted upon a pivot 15a and in an arm of this lever thereis engaged one arm of the lever 17 which is adapted to be oscillatedabout the spindle 2a and by its oscillation it imparts to the lever 15corresponding motion whereby the waver rollers are moved axially inorder to assist in the distribution of the ink on the surface of thecylinders 1 and 1a. The other arm of the lever 17 is provided with aroller 18- mounted on a pin 19 and engaging the slot 20 in the link 21which engages an eccentric 22 on the spur wheel 23 and is connected atthe other end with a pin joint 24 with the lever 25 pivotally mounted onthe pin 26 and oscillated about the said pin by the motion of theeccentric about the axis of rotation of the wheel 23 when the latter isrotated by rotation of the spur wheel 8.

The lever 25 is pivotally connected by the in 27 with the wedge shapedmember 28 and y the oscillation of the lever 25 the wedgeshaped memberis reciprocated. This motion of the wedge-shaped member between theroller 29 mounted upon the pin 30'and the roller 31 on the link 32 whichis provided with slots 33 and 34 engaging, respectively, the spindle 35on which the wheel 23 is mounted and the pin 30, causes the link to liftfrom the position shown in Figure 1 and in lifting it carries with it aplate 36 secured by the pin 37 to the link 32 thereby causing the hookedshaped portion 38 of the plate to engage the pin 39 on the arm 40 whichis connected to a similar arm on the o posite side of the machine by thebar 41 pivotally mounted in the side members of the frame of the machineand thus to move the arm in an upward direction about the axis' of thebar thereby raising the collars 42 with which they are pivotallyconnected by screws 43.

These collars are slidably mounted upon the rods 44 forming an extensionof the side members 45 of the carriage in which the pressure roller 46is mounted and between the collars and the upper portion of the sidemembers of the carriage, which are ivotal- 1y connected by the pins 47with t e arms 48 pivotally mounted on the pins 49 on the side frame ofthe machine, there are arranged springs 50 so that in the raising of thecollars the pressure roller will be caused to be resiliently pressed, inthe normal operation of the machine, on the sheet of paper or otherimpression-receivin material to be operated upon by the stencl Themember 51 extends between theflexible bands and is provided withfastening means 52 adapted to engage a stencil head ing, the body of thestencil being arranged in contact with a silk sheet 53 one end of whichis also en aged with the member 54 the other end 0 the silk sheet beingconnected with a substantially rigid element 55 extending from the bandon one side of the machine to a similar band on the other I side. Tothis rigid element which is not directly connected with these bands isconnected a flap 56 by a hinge pin 57 engaging in a turned over edge 58of the flap 56 and in lugs 59 on the rigid element.

On the flap 56 there are provided two rojections 60 and 6011 with theformer of w ich one end of a spring 61 and with the other, one end of asprin 61a is connected, the other ends of the spring being provided witha stirrup element 62, 62a which are engaged (see particularly Figures 2and 3) with the projections 63, 63a on the opposite ends of a vided withthe fastening means for the stencil heading.

In the normal operation of the machine, the flap 56 will be in theposition shown in Figure 2 and the flange 66 thereon will cooperate withthe adjacent edge of the rigid member 64. When occasion arises to re-mkthe machine the flap may be moved about its hinge into the positionshown in Figures 1 and 3 thus exposing a portion of the up er inkingcylinder 1a to the surface of which ink is applied. Thereafter the flapis moved into the position shown in Figure 2, being retained in thisposition by the tension of the springs and remaining in this positionduring the operation of forming stencil impressions, the springs alsooperating to draw the substantially rigid element 55 connected with oneend of the silk sheet 53, forward or towards the member 64 thusmaintaining the silk sheet taut.

What I claim is 1. A stencil carrier for rotary duplicating machines ofthe kind with which a relasecured, a rigid member connected to one endof said sheet and a hinged flap connected with the rigid member andsprings associated with the flap.

2. A stencil carrier for rotary duplicating machines of the kind withwhich a relatively viscous or pasty ink is employed comprising a sheetof flexible foraminous material in contact with which the stencil issecured, a rigid member connected to one end of said sheet and a hingedflap connected with the rigid member, a lug on one side of the rigidmember, a lug on the opposite side thereof, one end of a springconnected with one lug, a stirrup on the opposite end of said spring,one end of a spring connected with the second lug and a stirrup on theother end of said spring.

3. A stencil carrier for rotary duplicating machines having a flexibleforaminous stencil carrier, a rigid member connected to each end of saidstencil carrier, a hinged flap mounted to close the space between theends of said stencil carrier and springs associated with the flap tomaintain said flap closed and said carrier taut.

4. The combination with a rotary stencil duplicating machine havinginkingcylinders, and a flexible stencil carrier mounted to travel aroundsaid cylinders andhavinga rigid member connected to each end thereof, ofmeans for closing the space between the ends of said carrier com risinga flap hinged at one edge to one of said rigid members and adapted tobear at its opposite edge on the other rigid member and spring meansconnected between the flap and one of said rigid members adapted toyieldingly retain said flap in closed position.

5. The combination with a rotary stencil duplicating machine havinginking cylinders, and a flexible stencil carrier mounted to travelaround said cylinders and having a rigid member connected to each endthereof, of means for closing the space between the ends of said carriercomprising a flap hinged at one edge to one of said rigid members andadapted to bear at its opposite edge on the other rigid member, lugs onopposite sides of said flap, and springs arranged between said lugs andthe second mentioned rigid member to maintain the stencil carrier tautand the flap closed.

(5. The combination with a rotary stencil duplicating machine havinginking cylin- (lcrs, and a flexible stencil carrier mounted to travelaround said cylinders and having a rigid member connected to each endthereof, of means for closing the space between the ends of said carriercomprisin a fla hinged at one edge to one of said rigi mem ers andadapted to hear at its 0 posite edge on the other rigid member, andsprings connected between the edges of the fla and the second mentionedrigid member an adapted to pass IGMUND GESTETN'ER.

